The phase difference between two displacements at a certain point A at time `10^-3` sec apart is `pi`. Find the distance between point A and B, which is `60^@` out of phase than point A. If wave velocity is x:

Options

A. `1.33xx10^-3x`
B. `0.33xx10^-4x`
C. `2.33xx10^-4x`
D. `3.33xx10^-4x`

Answer

D

Explanation

`Delta phi=2pif(Delta t)impliespi=2pifxx10^-3`
`impliesf=500Hz` we have `Delta phi=k Delta x`
`Delta x=((Delta phi)lamda)/(2pi)=(((pi)/(3))((x)/(f)))/(2pi)=(x)/(6f)=3.33xx10^-4x`